Pasture patterns and associated soil water in partially cleared woodland

Abstract

Aerial photographs of parts of the Hunter Valley show many of the trees in the centre of a circle which is paler than the surroundings. The circles have been investigated through the aerial photographs and in the field, and appear to be related to the influence of tree roots upon the grasses in certain soils in regions of fairly low rainfall. No evidence of competition for soil water could be established in the relationship.